When SSC work as master, it will generate the frame sync signal. On old SoCs, it only supports frame sync length less or equal to 16bits, on newer SoCs, it supports frame sync length extension, which can support frame size larger than 16 bits. So, add this to make it supports playback 24/32 bits audio clips.

Signed-off-by: Bo Shen voice.shen@atmel.com --- include/linux/atmel-ssc.h | 4 ++++ sound/soc/atmel/atmel_ssc_dai.c | 34 ++++++++++++++++++---------------- 2 files changed, 22 insertions(+), 16 deletions(-)

diff --git a/include/linux/atmel-ssc.h b/include/linux/atmel-ssc.h index 9ee1b68..70c5922 100644 --- a/include/linux/atmel-ssc.h +++ b/include/linux/atmel-ssc.h @@ -72,6 +72,8 @@ void ssc_free(struct ssc_device *ssc); #define SSC_RFMR_DATNB_OFFSET 8 #define SSC_RFMR_FSEDGE_SIZE 1 #define SSC_RFMR_FSEDGE_OFFSET 24 +#define SSC_RFMR_FSLEN_EXT_SIZE 4 +#define SSC_RFMR_FSLEN_EXT_OFFSET 28 #define SSC_RFMR_FSLEN_SIZE 4 #define SSC_RFMR_FSLEN_OFFSET 16 #define SSC_RFMR_FSOS_SIZE 4 @@ -110,6 +112,8 @@ void ssc_free(struct ssc_device *ssc); #define SSC_TFMR_FSDEN_OFFSET 23 #define SSC_TFMR_FSEDGE_SIZE 1 #define SSC_TFMR_FSEDGE_OFFSET 24 +#define SSC_TFMR_FSLEN_EXT_SIZE 4 +#define SSC_TFMR_FSLEN_EXT_OFFSET 28 #define SSC_TFMR_FSLEN_SIZE 4 #define SSC_TFMR_FSLEN_OFFSET 16 #define SSC_TFMR_FSOS_SIZE 3 diff --git a/sound/soc/atmel/atmel_ssc_dai.c b/sound/soc/atmel/atmel_ssc_dai.c index de433cfd..7d501e4 100644 --- a/sound/soc/atmel/atmel_ssc_dai.c +++ b/sound/soc/atmel/atmel_ssc_dai.c @@ -347,6 +347,7 @@ static int atmel_ssc_hw_params(struct snd_pcm_substream *substream, u32 tfmr, rfmr, tcmr, rcmr; int start_event; int ret; + int fslen, fslen_ext;

/* * Currently, there is only one set of dma params for @@ -388,18 +389,6 @@ static int atmel_ssc_hw_params(struct snd_pcm_substream *substream, }

/* - * The SSC only supports up to 16-bit samples in I2S format, due - * to the size of the Frame Mode Register FSLEN field. - */ - if ((ssc_p->daifmt & SND_SOC_DAIFMT_FORMAT_MASK) == SND_SOC_DAIFMT_I2S - && bits > 16) { - printk(KERN_WARNING - "atmel_ssc_dai: sample size %d " - "is too large for I2S\n", bits); - return -EINVAL; - } - - /* * Compute SSC register settings. */ switch (ssc_p->daifmt @@ -413,6 +402,17 @@ static int atmel_ssc_hw_params(struct snd_pcm_substream *substream, * from the MCK divider, and the BCLK signal * is output on the SSC TK line. */ + + if (bits > 16 && !ssc->has_fslen_ext) { + dev_err(dai->dev, + "sample size %d is too large for SSC device\n", + bits); + return -EINVAL; + } + + fslen_ext = (bits - 1) / 16; + fslen = (bits - 1) % 16; + rcmr = SSC_BF(RCMR_PERIOD, ssc_p->rcmr_period) | SSC_BF(RCMR_STTDLY, START_DELAY) | SSC_BF(RCMR_START, SSC_START_FALLING_RF) @@ -420,9 +420,10 @@ static int atmel_ssc_hw_params(struct snd_pcm_substream *substream, | SSC_BF(RCMR_CKO, SSC_CKO_NONE) | SSC_BF(RCMR_CKS, SSC_CKS_DIV);

- rfmr = SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE) + rfmr = SSC_BF(RFMR_FSLEN_EXT, fslen_ext) + | SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE) | SSC_BF(RFMR_FSOS, SSC_FSOS_NEGATIVE) - | SSC_BF(RFMR_FSLEN, (bits - 1)) + | SSC_BF(RFMR_FSLEN, fslen) | SSC_BF(RFMR_DATNB, (channels - 1)) | SSC_BIT(RFMR_MSBF) | SSC_BF(RFMR_LOOP, 0) @@ -435,10 +436,11 @@ static int atmel_ssc_hw_params(struct snd_pcm_substream *substream, | SSC_BF(TCMR_CKO, SSC_CKO_CONTINUOUS) | SSC_BF(TCMR_CKS, SSC_CKS_DIV);

- tfmr = SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE) + tfmr = SSC_BF(TFMR_FSLEN_EXT, fslen_ext) + | SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE) | SSC_BF(TFMR_FSDEN, 0) | SSC_BF(TFMR_FSOS, SSC_FSOS_NEGATIVE) - | SSC_BF(TFMR_FSLEN, (bits - 1)) + | SSC_BF(TFMR_FSLEN, fslen) | SSC_BF(TFMR_DATNB, (channels - 1)) | SSC_BIT(TFMR_MSBF) | SSC_BF(TFMR_DATDEF, 0)

On 06/06/2014 09:41, Bo Shen :

Read SSC IP version to check whether it supports frame sync length extension feature.

Signed-off-by: Bo Shen voice.shen@atmel.com

No. We already have 2 compatible versions for the DT or id table. Simply add one. Please use this infrastructure to describe such features, I don't want to mix the approaches: "compatible string" xor "IP revision".

The DT of the product will then describe on which version of the IP it can rely to have this feature.

Best regards,

---

drivers/misc/atmel-ssc.c | 7 +++++++ include/linux/atmel-ssc.h | 3 +++ 2 files changed, 10 insertions(+)

diff --git a/drivers/misc/atmel-ssc.c b/drivers/misc/atmel-ssc.c index 22de137..9f49bcb 100644 --- a/drivers/misc/atmel-ssc.c +++ b/drivers/misc/atmel-ssc.c @@ -136,6 +136,7 @@ static int ssc_probe(struct platform_device *pdev) struct resource *regs; struct ssc_device *ssc; const struct atmel_ssc_platform_data *plat_dat;

• u32 version;

  ssc = devm_kzalloc(&pdev->dev, sizeof(struct ssc_device), GFP_KERNEL); if (!ssc) {

@@ -173,8 +174,14 @@ static int ssc_probe(struct platform_device *pdev) clk_prepare_enable(ssc->clk); ssc_writel(ssc->regs, IDR, -1); ssc_readl(ssc->regs, SR);

• version = ssc_readl(ssc->regs, VERSION); clk_disable_unprepare(ssc->clk);

• if (version >= 0x300)

• ssc->has_fslen_ext = 1;
  

• else

• ssc->has_fslen_ext = 0;
  

• ssc->irq = platform_get_irq(pdev, 0); if (!ssc->irq) { dev_dbg(&pdev->dev, "could not get irq\n");

diff --git a/include/linux/atmel-ssc.h b/include/linux/atmel-ssc.h index 571a12e..9ee1b68 100644 --- a/include/linux/atmel-ssc.h +++ b/include/linux/atmel-ssc.h @@ -19,6 +19,7 @@ struct ssc_device { int user; int irq; bool clk_from_rk_pin;

• int has_fslen_ext;

};

struct ssc_device * __must_check ssc_request(unsigned int ssc_num); @@ -258,6 +259,8 @@ void ssc_free(struct ssc_device *ssc); #define SSC_IMR_TXSYN_SIZE 1 #define SSC_IMR_TXSYN_OFFSET 10

+#define SSC_VERSION 0x000000fc

/* SSC PDC Receive Pointer Register */ #define SSC_PDC_RPR 0x00000100